Device and System for Condensing Gas

ABSTRACT

Various embodiments include an apparatus for liquefying gas comprising: an inlet for a pressurized gas; a countercurrent heat exchanger with a first channel for the pressurized gas to flow in a first direction; an expansion nozzle, such that the pressurized gas flows from the first channel into the nozzle, and flows out to form an aerosol comprising a gaseous phase and liquid droplets; an aerosol breaker separating at least some of the droplets out of the gaseous phase; a collecting region for gathering and collecting droplets dripping off the aerosol breaker; and a second channel of the countercurrent heat exchanger surrounding the first channel. The flow of the gaseous phase out of the expansion nozzle is colder compared to the gas flowing through the second channel in a second direction opposite to the first direction. The second channel surrounds the first channel. The apparatus comprises a monolithic structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Stage Application of International Application No. PCT/EP2018/081995 filed Nov. 21, 2018, which designates the United States of America, and claims priority to DE Application No. 10 2017 223 669.8 filed Dec. 22, 2017, the contents of which are hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to gas liquification. Various embodiments of the teachings herein may include apparatuses and/or plants for liquefying gas.

BACKGROUND

Plants and apparatuses for liquefying gas may be employed and used, for example, in a decentralized manner in energy transformation scenarios, in order, for example, to temporarily accept surplus electrical power generated and stored in a power grid and to convert it to an energy-storing medium, for example a liquid. This liquid is produced, for example, as cryogenic liquefied gas from the aforementioned gas. In other words, for example, the respective plant or apparatus can utilize surplus electrical power in order to liquefy the aforementioned gas and hence produce a liquid, especially in the form of cryogenic liquefied gas, from the gas. The liquid produced is, for example, liquid air, liquid natural gas, liquid nitrogen, liquid argon, and/or another liquid. This cryogenic liquefied gas may also be utilized for cooling of components from small generation plants in a decentralized manner, for example electrical assemblies with superconductive components.

However, such an apparatus or plant for liquefying gas typically has a multitude of components and is costly to manufacture, and so the decentralized liquefying of gas and hence utilization of surplus electrical power for liquefying of the gas is not yet economically viable to date. Plants or apparatuses for liquefying gas are currently space-intensive and cannot be reduced in size below a particular level without becoming uneconomic for the purposes of process technology in operation.

Furthermore, such plants or apparatuses are composed of a multitude of assemblies that have to be installed individually and connected to one another. Such components that have to be produced separately from one another and connected to one another are, for example, heat exchangers, a cryogenic storage tank, a throttle nozzle, insulation material, pipework, demisters or droplet separators, and further components. As a result, such plants or apparatuses are disproportionately costly in terms of their specific capacity-based capital costs.

However, the small plants or apparatuses operated in a centrally and fluctuating manner could enable a balance between supply and consumption in the electrical grid even at a local or regional level and, given correspondingly low specific operating and capital costs, bring about network buffering and the establishment of a storage product at the regional level, in which case the storage product produced from the gas may be the liquid mentioned. For applications with a low requirement for cooling at cryogenic temperatures colder than −100° C., there is likewise a need for a small, compact and easily operable production plant for cryogenic liquefied gas.

SUMMARY

The teachings of the present disclosure describe apparatuses and/or plants by means of which it is possible to liquefy gas efficiently and in a favorable manner in terms of space and costs. For example, some embodiments include an apparatus (26) for liquefying at least one gas, comprising: at least one inlet (30) via which the pressurized gas can be introduced into the apparatus (26); at least one countercurrent heat exchanger (32) having at least one first channel (34) that can be supplied with the pressurized gas via the inlet (30) and through which gas flow is possible in a first direction, at least one expansion nozzle (36) into which the first channel (34) opens, such that the gas that flows from the first channel (34) into the expansion nozzle (36), flows through the expansion nozzle (36) and flows out of the expansion nozzle (36) is expandable by means of the expansion nozzle (36) to form an aerosol comprising a gaseous phase and liquid droplets; an aerosol breaker (38) by means of which at least some of the droplets can be separated out of the gaseous phase; a collecting region (40) for gathering and collecting the droplets dripping off the aerosol breaker (38); and a second channel (42) of the countercurrent heat exchanger (32) that surrounds the first channel (34), wherein flow of the gaseous phase flowing out of the expansion nozzle (36) that has been decompressed and is colder compared to the gas through the second channel (42) is possible in a second direction that is the opposite of the first direction and the second channel (42) surrounds the first channel (34), wherein the apparatus (26) is in one-piece form.

In some embodiments, the apparatus (26) has an insulation (70) with at least one evacuated insulation jacket (72) that surrounds the countercurrent heat exchanger (32).

In some embodiments, the apparatus (26) has been produced by an additive manufacturing method, especially by methods of additive manufacturing or 3D printing.

In some embodiments, the respective channel (34, 42) runs in a spiral.

In some embodiments, the respective channel (34, 42) has at least a first channel section (60) and a second channel section (62) disposed on an inside (65) of the first channel section (60) facing the collecting region (40).

In some embodiments, the respective channel (34, 42) has a length of at least 10 meters.

In some embodiments, the aerosol breaker (38) has a multitude of funnel-shaped layers (64) arranged one on top of another, each with breaker plates (66) spaced apart from one another in circumferential direction of the aerosol breaker (38).

In some embodiments, the expansion nozzle (36) opens into a region (68) bounded by the aerosol breaker (38).

In some embodiments, the expansion nozzle (36) has a nozzle channel (80) which is bounded by an inner circumferential face (76) of a first nozzle body (78) of the expansion nozzle (36), and in which a second nozzle body (84) is disposed and is retained and spaced apart from the inner circumferential face (76) by means of lands (86) on the inner circumferential face (76), such that the inner circumferential face (76) and the second nozzle body (84) bound a nozzle cross section (90) that narrows in flow direction of the gas flowing through the nozzle channel (80).

In some embodiments, the apparatus (26) is formed from a metallic material.

As another example, some embodiments include a plant (10) for liquefying at least one gas, comprising at least one apparatus (26) as described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages, features, and details of the teachings of the present disclosure will be apparent from the description of a working example which follows, and from the drawings. The features and combinations of features mentioned above in the description and the features and combinations of features specified below in the description of figures and/or shown in the figures alone are usable not just in the particular combination specified but also in other combinations or on their own without leaving the scope of the teachings herein. The figures show:

FIG. 1 a schematic diagram of a plant incorporating teachings of the present disclosure for liquefying at least one gas;

FIG. 2 a schematic perspective view of an apparatus incorporating teachings of the present disclosure in the plant;

FIG. 3 a schematic longitudinal view of the apparatus;

FIG. 4 a schematic and perspective cross-sectional view of the apparatus;

FIG. 5 a detail of a schematic longitudinal section view of the apparatus;

FIG. 6 a schematic and perspective partial view of the apparatus;

FIG. 7 a schematic and perspective cross-sectional view of the apparatus;

FIG. 8 a further schematic and perspective cross-sectional view of the apparatus;

FIG. 9 a further schematic and perspective cross-sectional view of the apparatus;

FIG. 10 a further schematic and perspective cross-sectional view of the apparatus;

FIG. 11 a detail of a further schematic longitudinal section view of the apparatus;

FIG. 12 a detail of a further schematic longitudinal section view of the apparatus;

FIG. 13 a detail of a further schematic longitudinal section view of the apparatus;

FIG. 14 a detail of a further schematic longitudinal section view of the apparatus; and

FIG. 15 a detail of a further schematic longitudinal section view of the apparatus.

In the figures, elements that are the same or have the same function are given the same reference numerals.

DETAILED DESCRIPTION

Some embodiments of the teachings herein include an apparatus for liquefying at least one gas, such that a liquid is produced from the at least one gas in the course of the liquefying. The apparatus has at least one inlet via which the pressurized gas can be introduced into the apparatus. The apparatus also comprises at least one countercurrent heat exchanger having at least one first channel that can be supplied with the pressurized gas via the inlet and through which gas flow is possible in a first direction. The apparatus also has at least one expansion nozzle into which the first channel opens. As a result, the gas that flows from the first channel into the expansion nozzle, flows through the expansion nozzle and flows out of the expansion nozzle is expandable by means of the expansion nozzle to form an aerosol comprising a gaseous phase and liquid droplets. In other words, during the operation of the apparatus, the gas that flows through the expansion nozzle and flows out of the expansion nozzle is expanded by means of the expansion nozzle, which, below a gas-specific temperature, results in formation of an aerosol, also referred to as mist, from the gas. The aerosol comprises a gaseous phase and liquid droplets, with both the gaseous phase and liquid droplets formed from the gas flowing out of the expansion nozzle. The gaseous phase is thus at least a portion of the gas flowing through the expansion nozzle and flowing out of the expansion nozzle, without conversion of this portion into liquid or droplets, and this portion instead remaining in gaseous form.

In some embodiments, the apparatus additionally comprises an aerosol breaker by means of which at least some of the droplets can be separated out of the gaseous phase. In the course of this separating, for example, at least a portion of the droplets separates out in the aerosol breaker or precipitates on the aerosol breaker, as a result of which this portion is separated out of the aerosol.

In some embodiments, the apparatus additionally comprises a collecting region for gathering and collecting the droplets dripping off the aerosol breaker. The droplets dripping off the aerosol breaker can thus collect in the collecting region and form the aforementioned liquid, for example.

In some embodiments, the countercurrent heat exchanger further comprises a second channel that surrounds the first channel, through which flow of the gaseous phase flowing out of the expansion nozzle that has been decompressed and is colder compared to the gas is possible in a second direction that is the opposite of the first direction, and which surrounds the first channel. In other words, the gas that is not converted to liquid droplets by means of the expansion nozzle is expanded and becomes colder relative to the gas that has not yet flowed out of the expansion nozzle and is flowing through the first channel, for example, such that, for example, heat is transferred or can be transferred from the gas flowing through the first channel to the gaseous phase flowing through the second channel via respective wall regions of the countercurrent heat exchanger that each at least partly bound or form the channels. As a result, the gas flowing through the first channel is cooled and the gaseous phase flowing through the second channel or the gas flowing through the second channel is heated. In this way, the gas flowing through the first channel can be cooled particularly efficiently and effectively on its way to the expansion nozzle.

In some embodiments, the apparatus is in one-piece form. This means that the inlet, the countercurrent heat exchanger, the expansion nozzle, the aerosol breaker and the collecting region, or respective wall regions that form or bound the inlet, the countercurrent heat exchanger, the expansion nozzle, the aerosol breaker and the collecting region, are collectively in one-piece form, such that the apparatus takes the form of a monolith.

In this way, it is possible to keep both the costs and the number of parts, the weight and the space demands of the apparatus within a particularly small range, such that, for example, the apparatus can be utilized particularly advantageously for decentralized storage, especially intermediate storage, of surplus electrical power. More particularly, with the aid of the apparatus, it is possible to utilize surplus electrical power in a decentralized manner in order to form the liquid drops, also referred to as droplets, and hence the liquid from the at least one gas with the aid of the apparatus and with the aid of the surplus electrical power. In this way, it is possible to efficiently and effectively store at least a portion of the surplus electrical power in the liquid that takes the form, for example, of cryogenic liquefied gas. By virtue of the low space demands, it is also possible, in a decentralized manner, to produce a small amount of cryogenic liquefied gas from merely compressed gas, such that cooling of components to low temperature can be performed continuously solely from compressed gas.

In some embodiments, the gas is, for example, a working medium, it being possible to adapt the apparatus to different working media in a particularly simple manner. Possible working media are, for example, air, especially dry air, and nitrogen (N₂), oxygen (O₂), argon (Ar), krypton (Kr), xenon (Xe), neon (Ne), methane (CH₄), ammonia (NH₃), ethane (C₂H₆), ethylene (C₂H₄), propane (CH₃CH₂CH₃), propene (CH₂CHCH₃), carbon dioxide, especially pressurized carbon dioxide (CO₂), and other gases.

It is further possible to free compressed air of molecules that could solidify at the low temperatures of liquid air and hence block channels. This can be effected by suitable filters such as “molecular sieves”, which remove various absorbable molecules from the compressed air, for example short-chain hydrocarbons such as methane (CH4), ethane (C2H6), ethylene (C2H4), propane (C3H8), propene (C3H6), butane (C4H10), butene (C4H8), butadiene (C4H6), dinitrogen oxide (N2O, laughing gas), carbon dioxide (CO2) or water vapor (H2O).

In some embodiments, the one-piece configuration of the apparatus creates a design in which all functional parts required for liquefying of the gas are integrated. As a result, all that is still required for liquefying of the at least one gas is connection of a gas source that provides, for example, the at least one gas as pressurized gas to the apparatus at the inlet or via the inlet. In some embodiments, there is an outlet for the remaining depressurized gas that forms the gaseous phase, such that, for example, the apparatus may have an exit via which the gaseous phase can be discharged from the second channel or from the apparatus.

In some embodiments, the apparatus feeds the gaseous phase, especially via the exit, to a circulation system or a compressor that can compress the gaseous phase, for example. In this way, the compressor can, for example, convert the gaseous phase to the at least one gas, especially in the form of pressurized gas, such that the gaseous phase can then be supplied again as pressurized gas or as the at least one gas via the inlet of the apparatus and especially the first channel. By virtue of the one-piece configuration, it is also possible to assure a particularly high stability of the apparatus to high pressures. Moreover, no joining operations, screw connections, prefabricated parts, welds etc. are envisaged or required, since the apparatus is in one-piece form. The apparatus, especially its configuration, can be adapted in a parametrized manner to different gases and the respective volume thereof. More particularly, bundling of components in an additive manufacturing operation, for example in a geometry that can be built by PBF methods for jet melting in a powder bed (powder bed fusion) can be implemented without internal support structures.

In some embodiments, the apparatus is used to implement small plants utilizable in a decentralized manner for liquefying of gases and to operate such plants in a particularly economically viable manner. By virtue of the monolithic construction, it is also possible to implement encapsulation of the refrigeration energy of the liquid, such that particularly efficient operation can be achieved. Moreover, manual manufacture of the apparatus can be avoided. In other words, automatic, especially fully automatic, manufacture of the apparatus can be implemented, especially also when it has a complex geometry. This allows time- and cost-efficient manufacture of the apparatus.

In some embodiments, the apparatus has insulation with at least one evacuated insulation jacket that surrounds the countercurrent heat exchanger at least predominantly on the outside, especially completely. The insulation thus takes the form of a vacuum insulation since, for example, the evacuating of the insulation jacket results in such a vacuum within the insulation jacket that can be generated by industrially available means. What is more particularly understood to mean by the vacuum within the insulation jacket or the evacuating of the insulation jacket is thus that the pressure in the insulation jacket is significantly lower than a further pressure in the environment of the apparatus. Such a vacuum insulation can avoid excessive loss of refrigeration energy or excessive heat input into the storage region, such that the liquid, especially in the form of cryogenic liquefied gas, can be absorbed and stored particularly advantageously in the storage region.

In some embodiments, the apparatus has a removal connection via which the droplets or liquid can be removed from the collecting region to the environment of the apparatus.

In some embodiments, the apparatus has been manufactured by an additive manufacturing method, especially by 3D printing. More particularly, the apparatus has been formed by a powder bed fusion (PBF) method. Such an additive manufacturing method can build the apparatus merely in a self-supporting manner without internal support structures. Moreover, the apparatus can be produced in a time- and cost-efficient manner and with high stability and compressive strength.

In order to be able to keep the space demands of the apparatus particularly low and to achieve a particularly long length of the respective channel, in some embodiments, the respective channel runs at least essentially in the form of a spiral or helix, especially about a direction of longitudinal extent of the apparatus. This allows the gas flowing through the first channel to be cooled in a space-efficient and particularly efficient manner.

In some embodiments, the respective channel has at least a first channel section and a second channel section, with the second channel section arranged downstream of the first channel section in flow direction of the gas flowing through the respective channel, and with the channel sections connected fluidically to one another, for example. Said second channel section is disposed on an inside of the first channel section facing the collecting region. The use of the channel sections can achieve particularly long lengths of the channels in a space-efficient manner, such that especially the space demand extending in the direction of longitudinal extent of the apparatus can be kept within a particularly small range. Moreover, it is thus possible to cool the gas flowing through the first channel effectively and efficiently. In some embodiments, there are a third and fourth channel section.

In some embodiments, to achieve cooling of the gas flowing through the first channel, the respective channel has a length of at least 10 meters, e.g. of at least 20 meters, and in some cases, at least or exactly 21 meters.

In some embodiments, the aerosol breaker has a multitude of layers that are intrinsically or inherently funnel-shaped and are arranged one on top of another, each with breaker plates spaced apart from one another in circumferential direction of the aerosol breaker. In some embodiments, the respective layer is at least essentially funnel-shaped, for example, a respective envelope curve that delineates or surrounds the respective layer is at least essentially funnel-shaped, with the respective breaker plates of the respective layer arranged or accommodated, especially completely, in the respective envelope curve of the respective layer. The aerosol breaker here takes the form of a blossom of a flower, with the breaker plates, for example, forming respective petals of the blossom.

The layers and the breaker plates, for example, repeatedly deflect or divert the aerosol on its way from the expansion nozzle, for example, to at least one inflow opening via which the aerosol or the gaseous phase thereof can flow into the second channel by means of the aerosol breaker, such that a multitude of changes of direction of the aerosol is brought about. In this way, for example, the droplets incorporated in the aerosol can be separated out of the gaseous phase in the manner of a labyrinth seal, such that the gaseous phase entrains no liquid droplets or only a small number of liquid droplets and is transported into the second channel via the inflow opening. By means of the aerosol breaker, it is possible to separate the liquid droplets out of the aerosol in such a way that the liquid droplets of the aerosol, owing to the frequent changes of direction, precipitate on the breaker plates and, as a result, can run off the breaker plates and collect in the collecting region. As a result, the droplets form the cryogenic liquid which is produced from the gas.

In order to be able to particularly effectively and efficiently separate the droplets of the aerosol from the gaseous phase, in a further configuration of the invention, the expansion nozzle may open into a region bounded by the aerosol breaker. In other words, the expansion nozzle opens into an interior of the aerosol breaker, the interior of which is bounded, for example, from the outside by the breaker plates.

In some embodiments, the expansion nozzle has a nozzle channel which is bounded by an inner circumferential face of a first nozzle body of the expansion nozzle, and in which a second nozzle body is disposed. The second nozzle body is retained and spaced apart from the inner circumferential face by means of lands on the inner circumferential face and hence on the first nozzle body, with the lands spaced apart from one another, for example, in circumferential direction of the second nozzle body. As a result, for example, the gas flowing through the nozzle channel can flow between the inner circumferential face and the second nozzle body, especially an outer circumferential face of the second nozzle body. In addition, the inner circumferential face and the second nozzle body, especially the outer circumferential face thereof, bound a nozzle cross section that narrows in flow direction of the gas flowing through the nozzle channel, which means that the gas can be decompressed particularly effectively and efficiently and especially adiabatically by means of the expansion nozzle.

In some embodiments, the collecting region is surrounded at least partly on the outside, especially at least predominantly, by the countercurrent heat exchanger, such that the collecting region is surrounded, for example, not just by means of the insulation provided with preference, but especially by the gas to be cooled and/or the cold gaseous phase and hence insulated by means of the gas to be cooled or by means of the gaseous phase.

In some embodiments, the apparatus is formed from a metallic material. This can achieve a particularly high stability and strength, especially compressive strength, of the apparatus. Moreover, the at least one gas can be liquefied particularly efficiently and effectively, and it is possible to achieve advantageous insulation, especially of the collecting region.

Some embodiments include a plant for liquefying at least one gas, wherein the plant comprises at least one apparatus as described above. Advantages and advantageous configurations of the plant should be regarded as advantages and advantageous configurations of the apparatus, and vice versa. FIG. 1 shows, in a schematic diagram, a plant 10 for liquefying gas. The liquefying of the gas is understood to mean that a liquid 12 is formed or produced from the gas. In other words, the liquid 12 is formed at least from a first portion of the gas, and this takes the form, for example, of cryogenic liquefied gas. For example, it may be the case that a second portion of the gas different from the first portion is expanded and cooled, but is not converted to liquid and remains in gaseous form.

The plant 10 comprises, for example, a compressor 14 by means of which the at least one gas can be compressed or is compressed. The compressor 14 thus provides the at least one gas as pressurized gas. Rather than the compressor, it is also possible to use a pressurized gas storage means as gas source.

The pressurized gas—as illustrated by arrows in FIG. 1—is introduced via an exit valve 16 into a channel system 18 that runs through a heat exchanger unit 20. By means of the channel system 18, the gas is supplied as pressurized gas to an expansion valve 22 by means of which the gas is expanded and hence cooled. This produces the liquid 12 at least from the first portion of the gas, and this is liquid air, for example. For example, the second portion that remains in gaseous form is supplied to the heat exchanger unit 20 and flows around the channel system 18 in the heat exchanger unit 20, such that the gas flowing through the channel system 18 is cooled by means of the expanded and cooled second portion. The second portion is supplied, for example, via an inlet valve 24 to the compressor 14, such that, for example, the gas is formed as the pressurized gas from the second portion by means of the compressor 14, and this can be supplied or is supplied back to the channel system 18 via the inlet valve 24.

Downstream of the compressor 14 and upstream of the heat exchanger unit 20, an absorber unit 52 with two alternately switchable absorbers is provided for drying of the gas, which is also referred to as lead/lag switch.

The gas which is supplied to the compressor 14 and is compressed by means of the compressor 14 comes, for example, from the environment or from the atmosphere and is supplied to the compressor 14, for example via a gas inlet 25. In some embodiments, this has been or is stored in a gas reservoir 27 and is provided from the gas reservoir 27. The gas can then flow out of the gas reservoir 27 and be fed via the gas inlet 25 and, for example, the inlet valve 24 to the compressor 14.

To produce the liquid 12 particularly efficiently and effectively, and in a space- and cost-efficient manner, the plant 10 comprises an apparatus 26 that can be particularly readily discerned in FIGS. 2 to 15. The apparatus 26 is shown in a schematic perspective view in FIG. 2, and in a schematic longitudinal section view in FIG. 3. It is particularly readily apparent from FIG. 3 that the apparatus 26 has a direction of longitudinal extent illustrated by a double-headed arrow 28, which is also referred to, for example, as z direction.

It is particularly readily apparent from FIGS. 2 and 3 that the apparatus 26 has at least one inlet 30, also referred to as pressurized gas inlet, by means of which the at least one gas under pressure, i.e. the pressurized gas, can be introduced into the apparatus 26, for example via the inlet valve 24. In other words, during a process for liquefying the at least one gas, the gas under pressure is introduced into the apparatus 26 as pressurized gas via the inlet 30.

It is particularly readily apparent from FIG. 3 that the apparatus 10 has a countercurrent heat exchanger 32 which, for example, is the heat exchanger unit 20 or is used as the heat exchanger unit 20. The countercurrent heat exchanger 32 has at least one channel 34 that can be supplied with the pressurized gas via the inlet 30 and through which the gas can flow in a first direction, and, by virtue of the apparatus 26 in FIG. 3 being shown in a schematic longitudinal section view, respective parts of the channel 34 are apparent in FIG. 3. The channel 34 extends at least essentially in spiral form about the direction of longitudinal extent, such that, for example, the gas flows at least essentially in a spiral on its way through the channel 34.

The apparatus 26 additionally has at least one expansion nozzle 36 particularly readily apparent from FIG. 5, into which the first channel 34 opens. As a result, the gas that flows from the first channel 34 into the expansion nozzle 36, flows through the expansion nozzle 36 and flows out of the expansion nozzle 36 under pressure is expanded by means of the expansion nozzle 36, it being possible, given sufficient cooling of the gas in channel 34, for there to be expansion with formation of an aerosol comprising a colder gaseous phase formed from the gas and liquid drops or droplets. By means of the expansion nozzle 36, the gas is expanded and cooled, especially adiabatic, as a result of which, for example, at least the aforementioned first portion is condensed or liquefied and hence forms the liquid droplets. The gaseous phase of the aerosol is formed by the expanded and hence cooled gas itself, i.e. by the aforementioned second portion, while the gaseous phase or the gas that has not been converted to liquid becomes colder and is expanded compared to the gas flowing through the channel 34. The expansion nozzle 36 thus functions as the expansion valve 22.

The gaseous phase flows in the direction of an inlet opening 37 of the heat exchanger 32 which is intended for the expanded gas and, in this way, entrains the liquid droplets, for example. In order, however, to form the desired liquid 12 from the liquid droplets, the apparatus 26 comprises an aerosol breaker 38 by means of which at least a portion of the droplets can be separated out or is separated out of the gaseous phase of the aerosol. The aerosol breaker 38 results in a multitude of changes of direction and hence deflections of the flow of the aerosol, as a result of which, for example, at least a portion of the droplets is precipitated in the aerosol breaker 38. The droplets can then, for example, drip off the aerosol breaker 38 and collect in a collecting region 40. The apparatus 26 thus additionally includes the collecting region 40 gathering and collecting the droplets dripping off the aerosol breaker 38.

The countercurrent heat exchanger 32 additionally has at least a second channel 42 surrounding the first channel 34. Respective parts of the channel 42 are also apparent in FIG. 3, with the second channel 42 connected fluidically, for example, to the collecting region 40. More particularly, the second channel 42 has at least one inflow opening for the expanded gas, via which the second channel 42 is fluidically connected to the collecting region 40. This at least one inflow opening is, for example, the aforementioned inlet opening 37, via which the gaseous phase can flow into the second channel 42 and hence into the countercurrent heat exchanger 32. The aerosol or the gaseous phase flows out of the collecting region 40 to the inlet opening 37 and especially into the inlet opening 37, such that the gaseous phase flows into the second channel 42 via the inlet opening 37. The aerosol breaker 38 prevents the gaseous phase from entraining an excessive amount or number of droplets and transporting them into the second channel 42. The second channel 42 also extends at least essentially in a spiral about the direction of longitudinal extent, such that the gaseous phase flowing through the second channel 42 flows at least essentially in a spiral.

Since the respective channel 34 or 42 extends at least essentially in spiral form, the respective channel 34 or 42 has respective windings that extend around the direction of longitudinal extent. The feature that the second channel 42 surrounds the first channel circumferentially and completely, especially in its circumferential direction, is especially understood to mean that the respective windings of the channel 34 run in the respective windings of the channel 42, such that, for example, the second channel 42 forms at least one or more than one first spiral. In addition, the first channel 34 forms at least one or more than one second spiral, and, for example, the respective second spiral runs within the respective first spiral.

The gas that flows through the second channel 42 and forms the gaseous phase thus directly flows around the outside of respective walls or wall regions that form or bound the inside of the channel 34. This means that the colder gaseous phase compared to the gas flowing through the channel 34 is in direct contact with the walls mentioned, such that more efficient and more effective heat transfer from the warmer gas flowing through the channel 34 via the walls to the colder gaseous phase flowing through the channel 42 is possible. This means that the gas flowing through the channel 34 is cooled, and the gaseous phase flowing through the channel 42 is heated. Since the gas flows in the first direction and the gaseous phase in the opposite second direction, the heat exchanger unit 20 is designed as the effective and efficient countercurrent heat exchanger 32. Since the heat exchanger structure 32 is suspended with only few contact sites with the inner and outer wall, very good heat transfer takes place in spite of the small and compact design.

In some embodiments, the apparatus 26 is in the form of a monolith and hence in one-piece form. This allows the number of parts and hence the costs, the space required and the weight of the apparatus 26 to be kept within a particularly small range. In addition, it is also impossible for any leaks or cracks to occur at joining sites since the monolithic design reduces the number of connecting sites to a minimum of only 5 connections at most.

It is apparent from FIG. 2 that the apparatus 26 has at least one exit 44, also referred to as depressurized gas exit, via which, for example, the gaseous phase can be discharged from the second channel 42. Since the gaseous phase is expanded and hence decompressed compared to the gas flowing through the channel 34, the gaseous phase is also referred to as depressurized gas. The depressurized gas can be removed from the apparatus 26, for example via the exit 44. For example, the depressurized gas is fed back to the compressor 14 via the inlet valve 24, such that, for example, the depressurized gas can be compressed again by means of the compressor 14 as the aforementioned second portion.

The apparatus 26 may also have a burst valve connection 46 at which a burst valve, for example, can be attached. The burst valve connection 46 has a burst channel 48 apparent from FIG. 3, fluidically connected to the collecting region 40. If, for example, a pressure within the collecting region 40 exceeds a defined threshold, the burst valve opens, more particularly bursts, as a result of which the burst valve opens the burst channel 48, for example. As a result, for example, a fluid accommodated in the collecting region 40 can be removed from the collecting region 40 via the burst channel 48, such that any excessive pressure rise in the collecting region 40 can be avoided.

In order to manufacture the apparatus 26 in a particularly time- and cost-efficient manner, the apparatus 26 may be manufactured by an additive manufacturing method, especially by 3D printing.

FIG. 3 shows, for example, the apparatus 26 in its installed position, and FIG. 3 illustrates, by an arrow 50, a “direction of function” coinciding with the direction of longitudinal extent of the apparatus 26. Based on the installed position, gravity acts in the direction of function, since, for example, the drops deposited by means of the aerosol breaker 38 drip off from the aerosol breaker 38 in the direction of function and collect in the collecting region 40.

In addition, in FIG. 3, the arrow 50 illustrates a construction direction coinciding with the direction of longitudinal extent, in which the apparatus 26 is built or manufactured by the additive manufacturing method. The build of the apparatus 26 starts at the foot of the arrow 50 and grows in the direction of the tip of the arrow 50. By virtue of the monolithic configuration of the apparatus 26, it is possible to achieve the desired function thereof with regard to the liquefaction of the at least one gas, with the installed position in the direction of function being the opposite of the position in the direction of building, or vice versa.

In the ready-manufactured state, for example, the apparatus 26 is about as large as a football which is used as playing equipment or sports equipment in the sport of American Football. The apparatus thus enables decentralized, efficient, and effective liquefaction of gases, by means of which, for example, surplus electrical power can be stored, especially intermediately stored, in the liquid gas or liquid 12.

The inlet 30 comprises, for example, an inlet connection 54 of the apparatus 26, such that, for example, a conduit for guiding of the pressurized gas can be connected to the inlet connection 54. It is thus possible, for example, for the pressurized gas flowing through the conduit to flow out of the conduit and flow into the inlet connection 54, and via the inlet connection 54 into the channel 34.

In some embodiments, the apparatus 26 also has at least one exit 56 with at least one exit connection 58. Via the exit 56, the liquid 12, for example, can be removed from the collecting region 40. For this purpose, for example, a further conduit may be connected to the exit connection 58, such that the liquid 12 can flow out of the collecting region 40 and into the further conduit, especially via the exit connection 58. The exit 26 is thus an outlet for the liquid 12. For example, a valve, especially a low-temperature valve, may be connected to the exit connection 58, via which the liquid 12 can be removed from the collecting region 40.

The channel 34 and the channel 42 each have a first channel section 60 and a second channel section 62 disposed on an inside 65 of the first channel section 60 facing the collecting region 40. This means that the windings of the channel 34 or 42 that form the channel section 62 are arranged on the inside of the windings that form the channel section 60 of the channel 34 or 42. On its way from the inlet 30 to the expansion nozzle 36, for example, the gas flows through the channel section 60 of the channel 34 in the direction of function and hence downward with respect to the installed position, with the gas flowing in a spiral.

The gas flows here, for example, through the channel section 62 of the channel 34 counter to the direction of function and hence upward with respect to the installed position, with the gas flowing in a spiral through the channel section 62. Since the heat exchanger unit 20 is designed as the countercurrent heat exchanger 32, the gaseous phase flows, for example, on its way from the inflow opening mentioned to the depressurized gas exit through the channel section 60 of the channel 42, for example, counter to the direction of function and hence upward with respect to the installed position, and through the channel section 62 of the channel 42 in the direction of function and hence downward with respect to the installed position, such that the gaseous phase flowing through the channel 42 flows counter to the gas in the respective channel section 60 or 62. On its way from the inflow opening to the depressurized gas exit, the gaseous phase flows, for example, first through the channel section 60 of the channel 42 and then through the channel section 62 of the channel 42, or else first through the channel section 62 of the channel 42 and then through the channel section 60 of the channel 42. In this way, the gas can be cooled effectively and efficiently by means of the gaseous phase.

By means of the described arrangement of the channel sections 60 and 62 of the channels 34 and 42, it is possible to achieve particularly long lengths of the channels 34 and 42, while the space demands of the apparatus 26 can be kept particularly low. More particularly, the respective channel 34 or 42 preferably has a length of at least 10 meters, preferably of at least 20 meters.

As is particularly readily apparent from FIGS. 3 and 4, the aerosol breaker 38 has a multitude of at least essentially funnel-shaped layers 64 that are successive or arranged one on top of another, each with breaker plates 66 spaced apart from one another in circumferential direction of the aerosol breaker 38. The expansion nozzle 36 opens here into a region 68 bounded by the aerosol breaker 38.

In some embodiments, the apparatus 26 additionally has an insulation 70 with at least one evacuated insulation jacket 72 that at least predominantly surrounds the countercurrent heat exchanger 32 on the outside. Thus, the insulation 70 takes the form of a vacuum insulation. The vacuum insulation can achieve a particularly high energy efficiency without added costs. The vacuum insulation can create vacuum zones in order thus, for example, to thermally decouple different regions of the one-piece apparatus 26 from one another. The integrated aerosol breaker 38 preferably takes the form of a demister. More particularly, the collecting region 40 preferably has a capacity of about one liter of the liquid 12. The expansion nozzle 36 is also integrated into the apparatus 26 on account of the one-piece configuration thereof. By virtue of the construction of the apparatus 26, it is possible to achieve an intrinsically pressure-resistant construction with high heat exchange by virtue of tightly dimensioned wall lengths and by virtue of adjacent structures.

It is apparent from FIG. 2 that the apparatus 26 has a vacuum insulation connection 74. The vacuum insulation connection 74 can be used, for example, to insulate the insulation jacket 72; more particularly, an insulation valve and/or a conduit can be connected to the vacuum insulation connection 74, via which the insulation jacket 72 is evacuated or can be evacuated.

It is particularly readily apparent from FIG. 5 that the expansion nozzle 36 has a nozzle channel 80 which is bounded by an inner circumferential face 76 of a first nozzle body 78 of the expansion nozzle 36, and through which gas can flow. The nozzle channel 80 opens via an exit opening 82 of the expansion nozzle 36 into the aerosol breaker 38, especially into the region 68 bounded thereby.

The inner circumferential face 76 bounds a linear region 78 of the nozzle channel 80, with the linear region L narrowing in flow direction of the gas flowing through the nozzle channel 80.

In the nozzle channel 80 and especially at least in a portion of the linear region L is disposed a second nozzle body 84 of the expansion nozzle 36. Since the apparatus 26 is in one-piece form overall, the nozzle bodies 78 and 84 are collectively in one-piece form. The nozzle body 84 is retained on the inner circumferential face 76 and hence on the nozzle body 78 and spaced apart from the inner circumferential face 76 and from the nozzle body 78 by means of respective lands 86, such that the gas flowing through the nozzle channel 80 can flow between the nozzle body 78, especially the inner circumferential face 76, and the nozzle body 84, especially an outer circumferential face 88 of the nozzle body 84. The inner circumferential face 76 and the outer circumferential face 88 bound a nozzle cross section 90 through which the gas flowing through the nozzle channel 80 can flow, and which narrows in flow direction of the gas flowing through the nozzle channel 80 and hence toward the region 68.

FIG. 6 shows the apparatus 26 in a schematic partial view, with the exit 56 by the exit connection 58 being particularly readily apparent from FIG. 6.

FIG. 7 shows the apparatus 26 in a schematic cross-sectional view, with a conduit 92 through which the pressurized gas can flow and a conduit 94 through which the depressurized gas can flow being apparent in FIG. 7. The conduit 92 is, for example, part of the channel 34, while the conduit 94 is part, for example, of the channel 42. FIGS. 8 to 10 show the apparatus 26 in further perspective cross-sectional views. The layers 64 of the aerosol breaker 38 and the breaker plates 66 are particularly readily apparent from FIG. 9. The inlet 30 by the inlet connection 54, the burst valve connection 46, the vacuum insulation connection 74 and the exit 44 are particularly readily apparent from FIG. 10.

Finally, FIGS. 11 to 15 show the apparatus 26 in sections, in respective schematic longitudinal section views, in order, for example, to illustrate the vacuum insulation connection 74 also referred to as vacuum connection in detail. FIGS. 12 and 13 particularly clearly show, for example, holes 96 via which a material, for example, from which the apparatus 26 is manufactured especially by the additive manufacturing method and is not melted but remains in powder form in the course of the additive manufacturing method can be removed from the apparatus 26, especially from its interior, and conveyed to the environment of the apparatus 26. FIG. 15 shows the burst valve connection 46 in a detail view. The respective length of the respective channel 34 or is, for example, at least 21 meters, especially about 21.6 meters. The apparatus 26 is formed, for example, from a metallic material, with provision, for example, of an installed metal volume of about 4 liters, in order to manufacture the apparatus 26. 

What is claimed is:
 1. An apparatus for liquefying gas, the apparatus comprising: an inlet for a pressurized gas to be introduced into the apparatus; a countercurrent heat exchanger with a first channel supplied with the pressurized gas via the inlet and wherein the pressurized gas flows in a first direction; an expansion nozzle into which the first channel opens, such that the pressurized gas flows from the first channel into the expansion nozzle, and flows out of the expansion nozzle to form an aerosol comprising a gaseous phase and liquid droplets; an aerosol breaker separating at least some of the droplets out of the gaseous phase; a collecting region for gathering and collecting droplets dripping off the aerosol breaker; and a second channel of the countercurrent heat exchanger surrounding the first channel; wherein flow of the gaseous phase out of the expansion nozzle is colder compared to the gas flowing through the second channel in a second direction opposite to the first direction; the second channel surrounds the first channel; and the apparatus comprises a monolithic structure.
 2. The apparatus as claimed in claim 1, further comprising an evacuated insulation jacket surrounding the countercurrent heat exchanger.
 3. The apparatus as claimed in claim 1, wherein the apparatus comprises a monolithic structure fabricated using an additive manufacturing method.
 4. The apparatus as claimed in claim 1, wherein the first channel runs in a spiral.
 5. The apparatus as claimed in claim 1, wherein the first channel includes: a first channel section; and a second channel section disposed on an inside of the first channel section facing the collecting region.
 6. The apparatus as claimed in claim 1, wherein the first channel has a length of at least 10 meters.
 7. The apparatus as claimed in claim 1, wherein: the aerosol breaker comprises a multitude of funnel-shaped layers arranged one on top of another; and each funnel-shaped layer has associated breaker plates spaced apart from one another in circumferential direction of the aerosol breaker.
 8. The apparatus as claimed in claim 1, wherein the expansion nozzle opens into a region bounded by the aerosol breaker.
 9. The apparatus as claimed in claim 1, wherein: the expansion nozzle includes a nozzle channel bounded by an inner circumferential face of a first nozzle body of the expansion nozzle; and a second nozzle body is disposed within the inner circumferential face and is retained and spaced apart from the inner circumferential face by lands on the inner circumferential face; wherein the inner circumferential face and the second nozzle body bound a nozzle cross section narrowing in the flow direction of the gas flowing through the nozzle channel.
 10. The apparatus as claimed in claim 1, wherein the apparatus comprises a metal.
 11. (canceled) 